The present application relates to surface treatments for direct metal laser sintered materials and the like and, more particularly, to braze claddings for direct metal laser sintered materials.
Rapid prototyping techniques, such as direct metal laser sintering (“DMLS”), have been used to rapidly prototype and manufacture various mechanical parts, such as fuel nozzles and fuel circuits for aircraft engines. Rapid prototyping techniques typically operate by depositing multiple layers of material, thereby incrementally (i.e., in layers) forming the overall part. Each layer may be about 5 to about 100 pm thick, depending on the technique used and the type of material being deposited.
The DMLS process has been used to form metallic parts using a laser sintering process. In particular, the DMLS process precisely deposits metal powders in thin layers and the deposited powders are sintered by the laser, thereby forming a generally rigid layer. The metal powders may be steel-based powders, bronze-based powders or the like.
Despite the advantages (e.g., prototyping time savings) achieved by the DMLS process, direct metal laser sintered materials often are porous and include crevices, ridges, interconnected channels and other surface defects. The channels may potentially give rise to leaks (e.g., fuel leaks) and the surface defects may provide locations where particles and debris may be deposited, thereby obstructing fluid flow and/or causing turbulent flow. For example, surface defects may increase the tendency for coke formation in fuel circuits formed from direct metal laser sintered materials. Furthermore, direct metal laser sintered materials may be used in highly corrosive environments (e.g., as fuel nozzles in direct contact with fuel) and therefore may be subjected to chemical degradation.
Accordingly, there is a need for a system and method for treating the surface of direct metal laser sintered materials to improve corrosion resistance and reduce surface defects.